Sorry, I thought I had the diary for that period but it's for the 5th, not the 2nd.
The 2nd battalion were in the thick of the fighting when trying to repel the German offensive (Operation Michael) of March 1918, and were in constant action from 21st to 26th. The history reports that 20 officers, NCO's and men of the battalion were decorated for conspicuous bravery.
Given that the usual delay between an award and a mention in the Gazette was around three months, it seems likely that RSM Ross was one of those decorated for this action.